The suction-based fixture used as a device holder is ubiquitous nowadays. The suction cup usually includes a plurality of components and achieves suction through a two-tier suction mechanism. For example, a mechanical structure such as a cam action lever is used to pull the central portion of the suction cup away from the surface to be attached to for increasing the negative pressure between the suction cup and the surface to maintain the adsorption effect.
Because holding a mobile phone while driving is dangerous, some drivers use the device holder with suction cup to mount the top platform on the dashboard in the vehicle. However, as the optimal suction of the suction cup is on a flat, i.e., planar, smooth surface, while the top platform is always composed of a curved surface to achieve visual esthetics as well as certain design concerns, the curved surface may prevent the suction cup from completely sealing the surface area that the suction cup is attached to, the suction force is weakened and may cause the suction cup to fall off easily.